In an array substrate of a liquid crystal display device, an organic light-emitting diode (OLED) display device etc, respective gate lines may be controlled by a gate driving circuit (GOA). The gate driving circuit comprises a plurality of cascaded shift registers, wherein an output end of each stage of shift register is connected to one gate line and further connected to a next-stage shift register. Thus it can provide a trigger signal to the next-stage shift register simultaneously with providing a high-level conducting signal to the gate line. In this way, driving of a plurality of gate lines can be effected by means of a few of control signals.
Along with the improvement in the display panel size, resolution and refresh rate, gate lines in an array substrate have become longer and longer, resulting in signal delay from the resistance becoming greater and greater. Meanwhile, conducting time (e.g., the time of high level) of each gate line becomes shorter and shorter. This prevents the respective pixels connected to one gate line from sufficiently charging during its conducting time, thereby resulting in deficiencies in display such as ghosting.
In order to solve the above problem, a technique of making the conducting time of gate lines overlap is proposed. That is, when one gate line keeps conducting, there are other gate lines begin to conduct. Therefore, when the pixels connected to this gate line are charged, the pixels connected to other gate lines would first be “pre-charged”. In this way, a better charging effect may be achieved.
Obviously, when the resolution, refresh rate, etc. of the display panel are different, the desired overlapping rate of conducting time of gate lines is also different (e.g., the conducting time of two adjacent gate lines overlaps by ½ or ⅔). However, as for an existing gate driving circuit, in instances where its circuit structure (such as cascade relationship) is unchanged, it is impossible to achieve the purpose of changing the overlapping rate of the conducting time of gate lines by simply adjusting the control signals, thus the application effect thereof is limited.